Display screen or portion thereof with transitional graphical user interface



FIG. 1 is a front view of a first image in a sequence for a displayscreen or portion thereof with transitional graphical user interfaceaccording to a first embodiment; and

FIG. 2 is a front view of a second image in the sequence thereof;

FIG. 3 is a front view of a third image in the sequence thereof; and

FIG. 4 is a front view of a fourth image in the sequence thereof.

FIG. 5 is a front view of a first image in a sequence for a displayscreen or portion thereof with transitional graphical user interfaceaccording to a second embodiment; and

FIG. 6 is a front view of a second image in the sequence thereof;

FIG. 7 is a front view of a third image in the sequence thereof; and,

FIG. 8 is a front view of a fourth image in the sequence thereof.

The appearance of the transitional image sequentially transitionsbetween the images shown in FIGS. 1-4 and FIGS. 5-8. The process orperiod in which one image transitions to another image forms no part ofthe claimed design.

The outermost broken line rounded rectangle showing an electronic deviceillustrates environmental subject matter. The broken line showing adisplay screen, and all other broken lines showing portions of thegraphical user interface illustrate portions of the article. None of theaforementioned broken line subject matter forms part of the claimeddesign.

CLAIM The ornamental design for a display screen or portion thereof withtransitional graphical user interface, as shown and described.